feat: update policy protobufs

Policy component's protobufs are updated based upon
the Event Condition Action (ECA) model.
Minor fixes are applied to the slice.proto in order
to compile.

Signed-off-by: Georgios Katsikas <katsikas.gp@gmail.com>

proto/.gitignore

+src/
+uml/generated

proto/compile.sh

 #!/bin/bash
 python3 -m grpc_tools.protoc -I=./ --python_out=src/ --grpc_python_out=src/ *.proto
 #requires installation of protoc-gen-uml
-export PATH=/home/osboxes/protoc-gen-uml/target/universal/stage/bin:$PATH
+export PATH=${HOME}/protoc-gen-uml/target/universal/stage/bin:$PATH
 protoc --uml_out=uml/ -I ./ *.proto
 cd uml
 java -jar plantuml.7997.jar *.puml

proto/policy.proto

@@ -2,7 +2,6 @@ syntax = "proto3";
 package policy;
 
 import "context.proto";
-import "service.proto";
 
 service PolicyService {
   rpc PolicyAdd (PolicyRule) returns (PolicyRuleState) {}
@@ -10,53 +9,77 @@ service PolicyService {
   rpc PolicyDelete (PolicyRule) returns (PolicyRuleState) {}
   rpc GetPolicy (PolicyRuleId) returns (PolicyRule) {}
   rpc GetPolicyByDeviceId (context.DeviceId) returns (PolicyRuleList) {}
-  rpc GetPolicyByServiceId (service.ServiceId) returns (PolicyRuleList) {}
+  rpc GetPolicyByServiceId (context.ServiceId) returns (PolicyRuleList) {}
 }
 
-message PolicyRuleList {
-  repeated PolicyRule policyRuleList = 1;
+enum RuleState {
+  POLICY_INACTIVE = 0;    // Rule is currently inactive
+  POLICY_PLANNED = 1;     // Rule installation planned
+  POLICY_ACTIVE = 2;      // Rule is currently active
 }
 
-//according to IETF’s RFC 3060 [] and RFC 3460 []
-message PolicyRule {
-  PolicyRuleId policyRuleId = 1;
-  repeated service.ServiceId serviceList = 2;
-  repeated context.DeviceId deviceList = 3;
-  string policyRuleType = 4;
-  string PolicyRulePriority = 5;
-  repeated PolicyRuleCondition polRuleConditionList = 6;
-  repeated PolicyRuleAction polRuleActionList = 7;
+enum PolicyRuleType {
+  POLICYTYPE_DEVICE = 0;  // Device-level
+  POLICYTYPE_NETWORK = 1; // Network-wide
 }
 
-message PolicyRuleId { 
+message PolicyRuleId {
   context.Uuid uuid = 1;
 }
 
+message PolicyRuleState {
+  context.Uuid policyRuleId = 1;
+  RuleState policyRuleState = 2;
+}
+
+message PolicyRuleVariable {
+  string policyRuleVariable = 1;
+}
+
+message PolicyRuleValue {
+  string policyRuleValue = 1;
+}
+
+// IETF draft: Framework for Use of ECA (Event Condition Action) in Network Self Management
+//     Source: https://datatracker.ietf.org/doc/draft-bwd-netmod-eca-framework/
+// Event
+message PolicyRuleEvent {
+  context.Event event = 1;
+}
+
+// Condition
 message PolicyRuleCondition {
   PolicyRuleVariable polRuleConditionVar = 1;
   PolicyRuleValue polRuleConditionVal = 2;
 }
 
+// Action
 message PolicyRuleAction {
   PolicyRuleVariable polRuleActionVar = 1;
   PolicyRuleValue polRuleActionVal = 2;
 }
 
-message PolicyRuleVariable {
-  string policyRuleVariable = 1;
-}
+// Policy rule partially complies with IETF’s:
+//     RFC 3060: https://datatracker.ietf.org/doc/html/rfc3060
+//     RFC 3460: https://datatracker.ietf.org/doc/html/rfc3460
+// Enhanced with a policy rule event according to the ECA model
+message PolicyRule {
+  // Basic policy rule attributes
+  PolicyRuleId policyRuleId = 1;
+  PolicyRuleType policyRuleType = 2;
+  uint32 PolicyRulePriority = 3;
 
-message PolicyRuleValue {
-  string policyRuleValue = 1;
-}
+  // Event-Condition-Action model
+  PolicyRuleEvent event = 4;                             // A single event triggers the policy
+  repeated PolicyRuleCondition polRuleConditionList = 5; // One or more conditions must be met
+  repeated PolicyRuleAction polRuleActionList = 6;       // One or more actions should be applied
 
-message PolicyRuleState {
-  context.Uuid policyRuleId = 1;
-  RuleState policyRuleState = 2;
+  // Affected services and devices
+  repeated context.ServiceId serviceList = 7;
+  repeated context.DeviceId deviceList = 8;
 }
 
-enum RuleState {
-  PLANNED = 0;
-  ACTIVE = 1;
+// A list of policy rules
+message PolicyRuleList {
+  repeated PolicyRule policyRuleList = 1;
 }
-

proto/slice.proto

@@ -3,24 +3,21 @@ syntax = "proto3";
 package slice;
 
 import "context.proto";
-import "service.proto";
 
 service SliceService {
-  rpc CreateUpdateSlice ( TransportSlice ) returns (SliceStatus) {}
-  rpc DeleteSlice ( TransportSlice ) returns (context.Empty) {}
+  rpc CreateUpdateSlice (TransportSlice) returns (SliceStatus) {}
+  rpc DeleteSlice (TransportSlice) returns (context.Empty) {}
 }
 
-
 message SliceEndpoint {
   context.EndPoint port_id = 1;
 }
 
-
 message TransportSlice {
   SliceId slice_id = 1;
   repeated slice.SliceEndpoint endpoints = 2;
   repeated context.Constraint constraints = 3;
-  repeated service.ServiceId services = 4;
+  repeated context.ServiceId services = 4;
   repeated SliceId subSlicesId = 5;
   SliceStatus status = 6;
 }